A Man's Partner

Detective Jericho's former partner, Mickey "Mouse" Davis, with whom he worked in NYPD Homicide, is found dead in his car - killed by a single gunshot fired into his mouth. A handwritten suicide note is discovered beside him. NYPD declares Mouse's death a suicide, but Jericho has his doubts. He takes time off from his East Hampton Police Department work and goes into the city to investigate. The New York cops tell Jericho to stay out of it, so Jericho must try to solve this case on his own.

As Sam Spade says in The Maltese Falcon "When a man's partner is killed, he's supposed to do something about it."